Plugged Drain Hose On Vent - 95 Pickup

There is a leak in the interior of my '95 Nissan 4x4 Extended Cab Pickup. It
is clear (no antifreeze odor or color), and only occurs when it rains, or

the AC is on. Because of that I have deduced that the drain hose must be the
cause of my interior leak. To save me the hassle of researching where the
hose is, and the best method to clear it, I would appreciate counsel from
anyone that might have experienced the same problem, or anyone that knows
the procedure to remedy the issue. It would also be helpful to know where
the drain end of the hose is positioned.
Thank you.
Louis--
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Remove the two fish in address to respond

I believe the drain tube is actually *in* the cab of the truck. Best way
to clear it is to possibly put a small brush, like a pipe cleaner, up it
and scrub it out. Better to do it soon so that it doesn't mold up, etc....
www.nissanfrontier.net

I agree that it makes no sense. Here is the best I can do; back in the
'80's my dad had a Pontiac GrandAm, and it always smelled wet inside.
That condensation drain got plugged about once every month in the
summer. It was a 5/8" tube located on the firewall directly in front of
the passenger foot well.

I posted this about a year ago in this NG. It sounds like something else
but keep reading.
I had the same problem with a 97 Nissan Pickup. I noticed a strange
rubbing noise in the right front only when making a left turn. It
sounded like it was the right front tire rubbing against a loose inner
splash shield in the fender when the wheel turned to the left. Upon
inspection, I could not find anything wrong up there. I had planned to
take the truck to my mechanic to find the source of the noise later in
the week. A day or so later, I picked up a box containing something I
had bought and had left on the passenger side floor overnight. I noticed
that the box was soaking wet on the bottom half. I then felt the floor
mats and they were drenched. Having had this problem in other cars that
I have owned, I assumed that it was a clogged drain hose. I looked under
the dash and saw water slow dripping from the air plenum. I pulled the
drain hose that runs from the plenum through the firewall and water
poured out of it. I cleaned the coagulated debris out of the drain hose
and replaced it. I also pulled the other rubber hose that ran between
the air plenum and the blower motor under the dash and about a pint of
water ran out of that hose.

It is on the firewall on the passenger side. Jack up the truck and look
for the short hose that sticks through the firewall and then get a wire
and put it in the hose to clear the blockage. Do not stick it in hard
or too far as not to damage the A/C core
Louis Bybee wrote:

No need to jack up the truck. You can get it from inside the cab. Look
under the dash on the passenger side. You'll see a large black plastic
box hanging from behind the dash between the glove box and center floor
hump. Reach under it and put your hand all the way to the back of the
box near the center floor hump. You'll feel a soft black plastic hose
(about 1/2" thick) running from the bottom of the box and going into the
firewall. It's only a couple of inches long from the box to the
firewall. You can start by pumping that hose with your thumb and finger
to see if you can push out whatever is blocking it. If not, get a pan or
something to catch the water, and pull the hose from the box towards the
firewall until it comes off the box (and drops water into the pan). Now
pull the loose hose from the firewall and clean it out. Reinstall by
pushing the hose back into the firewall hole and then onto the box. Now
pull off the hose on the bottom of the heater fan motor under the dash
by the passenger door. Keep that pan handy in case there is water in
there too. If no water comes out, put it back on.

It
the
Well I quit procrastinating, and crawled under the passenger dash to check
out all the information I received.
The two hoses were exactly where people said they would be. The hose through
the firewall was plugged tight, and when I pulled it off about 1 quart of
water poured out. I tried pushing through the hose to clear it out, but
wasn't having much luck. I pulled the hose back through the firewall, and it
had a 90 degree bend towards the end of the hose (that would explain the
difficulty clearing the hose). I cleaned it out, flushed the housing out,
and replaced the hose. The hose to the blower motor didn't have any moisture
in it. What purpose does that hose serve?
No more leak! :o)
Thanks to all who responded.
Louis--
*********************************************
Remove the two fish in address to respond

I believe it is just an air hose for the fan motor. The reason I had
water in there was because there was so much water in the air plenum
that it had run down into the motor housing.
Sorry I didn't tell you about that bend in the drain hose. I had
suggested you pull it out from the firewall to clean it.
Glad you got it worked out anyway.

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